The invention relates to a device for locking a power tool to a battery pack, and also relates to a battery pack.
Known locking devices for locking cordless power tools, such as handheld power drills, drill hammers, and the like, to a battery pack serving to supply current to them, have one or more locking bars in most cases, which are each supported movably, counter to the force of a spring, in a housing of the power tool and are brought by the spring force into engagement with a detent recess in the battery pack when the battery pack is thrust into a guide of the power tool, in order to connect the battery pack to the power tool. For undoing the connection, the housing of the power tool is equipped with an unlocking device, which is typically located, in the form of a push button, in the vicinity of the guide and is actuated by hand in order to disengage the locking bar from the detent recess.
In another known locking device, which makes so-called one-handed operation of the battery pack possible, the locking bars and the springs that act on the locking bars are integrated, together with two unlocking buttons serving to release the battery pack, with the battery pack, so that when the battery pack is released, the power tool can be firmly held with one hand while the battery pack is grasped with the other hand, the two locking bars are disengaged by finger pressure or thumb pressure on the unlocking buttons from the detent recesses that are recessed out of the housing of the power tool, and the battery pack can then be pulled out of the guide of the power tool. This kind of one-handed operation is indeed sought, but it has the disadvantage that the production costs for the battery pack are higher because of the integration of the locking bars, springs and unlocking devices, and because of the requirement for higher-precision tolerances. Nevertheless, the battery pack should be as inexpensive as possible, since most customers consider the battery pack, unlike the power tool, to be a disposable item that has to be replaced after a certain time in use. The readiness to buy a new battery pack is all the greater, the more inexpensively the battery pack can be procured. Moreover, because of the integration of the locking bars, springs and unlocking devices with the battery pack, the requisite installation space and the weight of the battery pack are increased, which is also seen as a disadvantage.